Reciprocating floor conveyors are generally employed for transport of liquid bearing material such as, for example, garbage. Liquid impermeable reciprocating floor conveyors comprised of a plurality of slat groups are known in the art. These liquid-tight reciprocating floor conveyors are often employed in containers such as truck or trailer boxes, transport containers, or fixed installation containers, each having a bottom, two sides, two ends (one of which is openable), and, optionally a top. The liquid-tight reciprocating floor conveyor is supported by the bottom of the container.
Drive mechanisms for reciprocating floor conveyors are generally located under the slats of the reciprocating floor. However, such a drive mechanism location is inappropriate for liquid impermeable reciprocating floor conveyors. Mounting a drive mechanism underneath a liquid-tight reciprocating floor conveyor is extremely laborious, and very costly. Specifically, an extensive hose and tubing system is required to connect the hydraulic fluid supply located at the front of the container to the drive units located underneath the reciprocating floor conveyor. Furthermore, to install the drive mechanism underneath the reciprocating floor conveyor requires that the container bottom have large openings therein. These openings compromise the structural integrity of the container bottom which results in bending and shear forces being translated from this unstable container bottom to the slats of the reciprocating floor conveyor; the result being excessive slat wear and damage.
U.S. Pat. Nos. 5,125,502 and 5,096,356 issued to Foster disclose a drive mechanism for a reciprocating floor conveyor which is located not underneath, but at an end of the reciprocating floor conveyor. The Foster conveyor comprises a plurality of elongated load supporting floor members supported for longitudinal back and forth movement within a material receiving compartment. A drive assembly compartment is provided at one end of the material receiving compartment. A bulkhead is positioned between the material receiving compartment and the drive assembly compartment. A plurality of piston-cylinder drive units are positioned within the drive assembly compartment. Each drive unit is associated with a separate set of the floor members. The drive units are operated to move the floor members longitudinally. Each drive unit includes longitudinally extending drive rods, one for each of its floor members. The drive rods extend from the drive units through the bulkhead, into the material receiving compartment and are connected to the floor members within the material receiving compartment. The bulkhead is provided with a plurality of bushings, one for each drive rod. The drive rods extend through the bushings. The bushings include seals for sealing against liquid leakage from the material receiving compartment, through the bushings, and into the drive assembly compartment.
The above Foster drive mechanism suffers from the following shortcomings. First, the drive mechanism is located within the container itself, thus decreasing the effective slat length of the reciprocating floor conveyor available, which decreases the volume of the load to be carried in a given container. Additionally, the location of the drive mechanism within the container results in limited access to the drive mechanism for repair and maintenance. Second, Foster employs one drive rod for each slat of the reciprocating floor conveyor. This configuration is unduly complex, thus being susceptible to component failure and is unduly costly. More importantly, the excessive number of drive rods results in numerous openings in the bulkhead through which the drive rods pass to their connected slats. Every one of these openings in the bulkhead is potential source of liquid leakage. Third, each bulkhead opening requires a bushing which surrounds the drive rod. These bushings are another potential source of liquid leakage.
Finally, U.S. Pat. No. 4,966,725 issued to Hallstrom, Jr., U.S. Pat. No. 5,000,647 issued to Foster, and U.S. Pat. No. 5,092,732 issued to Foster all disclose reciprocating floor conveyors having a separable floor unit and power drive unit with the power drive unit located under the container that houses the floor unit.
A need thus exists for a drive mechanism for a reciprocating floor conveyor in which the drive mechanism is located at an end of the reciprocating floor conveyor container.
A need exists for a reciprocating floor conveyor having a separable floor unit and drive mechanism wherein the drive mechanism is located at an end of the container that houses the floor unit.
A need exists for a drive mechanism for a reciprocating floor conveyor in which the drive mechanism includes a number of drive rods equal to the number of cross-members employed, and not equal to the total number of slats employed, in order to reduce complexity and cost of the mechanism and to minimize the number of openings in the partitioning bulkhead to minimize liquid leakage.
A need also exists for the above type of reciprocating floor conveyor drive mechanism in which bushings in the partitioning bulkhead openings which surround the drive rods are not necessary, thus further reducing the chance of liquid leakage.